Customization of Inner Sole Board

ABSTRACT

An inner sole board having varying regions of flexibility is provided for use in an article of footwear. The inner sole board may include different materials along its length at different locations that vary its flexibility. An inner sole board is manufactured in an injection molding process requiring only one mold. The process includes a first step of providing a mold, a second step of providing an injection molding assembly, a third step of preparing an injection molding assembly and mold, a fourth step of injecting material into the mold, and a fifth step of establishing the dimensions of a first portion. During the injection molding process, the flow rate of at least one material may be controlled by a nozzle gate to control the shape and size of the flex zone it creates. In this manner, the inner sole board may be customized for a specific sport or individual.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an inner sole board, and morespecifically to a customizable inner sole board.

2. Description of Related Art

Generally, soles and sole portions may be designed to provide supportand protection, prevent injury, and correct or mitigate foot and otherbodily ailments. Articles of footwear, for example, athletic shoes, maybe designed to have soles or sole portions of varying flexibility toprovide the support typically needed for a particular activity or sport.For example, soccer cleats are typically rigid in the posterior and moreflexible in the forefoot region. However, football cleats tend to bemore rigid in the forefoot region, in part to prevent turf toe injuries.

Different sole structures have been proposed. U.S. Pat. No. 3,444,586 toDubner teaches a shoe made with a quick setting material that may beinjected into the shoe to increase foot comfort. The Dubner shoe has anupper flexible portion, a sole, a heel, a sock lining, and a shank. Theshank and sole have an opening through which molding material may beinjected into the shoe. The sole interior includes four recesses andeach recess accommodates a molding material receiving bag. The fourreceiving bags are in fluid communication with the opening and receivemolding material upon injection. An injection means, including aninjection gun, engages with the shoe at the opening to fill tworeceiving bags at a time. The material in two of the bags are filled andset while the wearer is sitting, and the material in the remaining twobags are filled and set while the wearer is walking.

U.S. Patent Application Number 2006/0242860 to Canvin teaches a thickinsole with cavities able to receive inserts so that the hardness of theheel, arch, and metatarsal regions can be customized for a particularwearer. The insole has a main body with a bottom side having twocavities. A first cavity, the metatarsal cavity, mates with a metatarsalinsert. A second cavity, the heel and arch cavity, mates with a heel andarch insert. The main body and inserts are separately made and compriseinjection-molded foam. In order to provide variations in the hardness ofthe insole, the inserts may be formed of a different material than themain body. An article of footwear may be sold as a kit with multiplesets of interchangeable insoles. Each set of insoles is sized for thefootwear and varies with respect to the durometer of the inserts or thedurometer main body. The shape and size of portions of the insole mayalso be varied.

UK Patent Application GB2136671A to Buller teaches an injection moldedinsole having increased flexibility in the forepart. The insole has aforepart, a waist region, and a rear region. Generally, the insole isintegrally formed through an injection molding process. The forepart isrelatively thin and includes an aperture. As a result, the forepart ismore flexible than the remainder of the insole. The portion of theforepart surrounding the aperture is the peripheral zone. In anotherembodiment, the aperture may be covered by a thin web of material. Theinsole, including the aperture or the web, is injection molded using onemold. In other embodiments, the aperture may be occupied by a fillercomprising a foam plastic material. The filler is either formed andinserted into the aperture after the injection molding process or addedinto the mold before the injection molding process so that the fillerbonds to the mold material during the molding process.

In general, footwear having soles with varying flexibilitycharacteristics are known in the art. Soles using multiple materials arealso generally known. However, the flexibility characteristics of thesesoles generally cannot be controlled when multiple materials areinjected into a single mold. In particular, controlling the size andshape of at least one of the co-molded materials during the co-moldingprocess is not known. Therefore, there is a need in the art for a systemand method that addresses the shortcomings of the art.

SUMMARY OF THE INVENTION

An inner sole board and method of making an inner sole board aredisclosed.

In one aspect, an inner sole board for an article of footwear comprisesa first portion comprising a first material, a second portion comprisinga second material, and a bonding zone disposed where the first portionand the second portion meet. The first material having differentflexibility characteristics than the second material. The size and thelocation of the first portion with respect to the second portion isconfigured to conform to a set of flexibility characteristics associatedwith an activity. The bonding zone comprises a bond between the firstmaterial and the second material that is initiated when the firstmaterial and second material are in a molten state.

In another aspect, the first portion is disposed in a forefoot region ofthe article of footwear.

In another aspect, the first portion is disposed in a heel region of thearticle of footwear.

In another aspect, the first portion has a first thickness, the secondportion has a second thickness, and the first thickness and the secondthickness are substantially equal proximate the bonding zone.

In another aspect, the first portion has a circular shape.

In another aspect, the first portion is substantially coextensive withthe forefoot region.

In another aspect, a kit for customizing an article of footwearcomprises a group of inner sole boards wherein each inner sole board ofthe group of inner sole boards is configured to be removably insertedinto the article of footwear.

In another aspect, each inner sole board has a unique flexibilitycharacteristic.

In another aspect, each inner sole board comprises a first portioncomprising a first material, a second portion comprising a secondmaterial, and a bonding zone disposed where the first portion and thesecond portion meet.

In another aspect, the first material having different flexibilitycharacteristics than the second material.

In another aspect, the size and location of the first portion withrespect to the second portion is configured to conform to a set offlexibility characteristics associated with an activity.

In another aspect, the bonding zone comprises a bond between the firstmaterial and the second material that is initiated when the firstmaterial and second material are in a molten state.

In another aspect, the group of inner sole boards comprise left-footinner sole boards.

In another aspect, the group of inner sole boards comprise right-footinner sole boards.

In another aspect, the kit comprises left-foot inner sole boards andright-foot inner sole boards.

In another aspect, the method of making an inner sole board comprisingthe steps of providing a mold having a single cavity; providing aninjection molding assembly comprising a first nozzle and a secondnozzle; injecting into the cavity a first molten material through thefirst nozzle and a second molten material through the second nozzle sothat the first molten material forms a first portion of the inner soleboard and the second molten material forms a second region of the innersole board; and establishing dimensions of the first portion bycontrolling the first nozzle.

In another aspect, the dimensions of the first portion are establishedby controlling a first flow rate through the first nozzle.

In another aspect, the dimensions of the first portion are establishedby controlling a first nozzle time on and a first nozzle time off.

In another aspect, the dimensions of the first portion are establishedby controlling the second nozzle.

In another aspect, the dimensions of the first portion are establishedby controlling a second nozzle time on and a second nozzle time off.

In another aspect, the dimensions of the first portion are establishedby staggering the first nozzle time on and the second nozzle time on.

In another aspect, the dimensions of the first portion are establishedby staggering the first nozzle time off and the second nozzle time off.

In another aspect, the first material and second material form a bond ina bonding zone at a temperature greater than or equal to a bondingtemperature.

In another aspect, the first material and the second material aredelivered into the cavity simultaneously.

In another aspect, the bond is selected from a group consisting of achemical bond and a mechanical bond.

Other systems, methods, features and advantages of the invention willbe, or will become, apparent to one of ordinary skill in the art uponexamination of the following figures and detailed description. It isintended that all such additional systems, methods, features andadvantages be included within this description and this summary, bewithin the scope of the invention, and be protected by the followingclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood with reference to the followingdrawings and description. The components in the figures are notnecessarily to scale, emphasis instead being placed upon illustratingthe principles of the invention. Moreover, in the figures, likereference numerals designate corresponding parts throughout thedifferent views.

FIG. 1 is a schematic isometric view of one embodiment of a cleatedarticle of footwear;

FIG. 2 is a schematic isometric exploded view of one embodiment of acleated sole;

FIG. 3 is a schematic isometric view of one embodiment of an inner soleboard;

FIG. 4 is a schematic cross-sectional diagram of the inner sole boardshown in FIG. 3, taken along line 4-4;

FIG. 5 is a schematic enlarged cross sectional diagram of the inner soleboard shown in FIG. 3, taken along line 5-5;

FIG. 6 is a schematic diagram of one embodiment of a process for makingan inner sole board;

FIG. 7 is a schematic isometric view of one embodiment of a two-partmold with one part rotated so that the mold is open;

FIG. 8 is a schematic isometric view of one embodiment of an injectionmolding assembly and a mold;

FIG. 9 is a schematic cross-sectional diagram of a portion of theinjection molding assembly shown in FIG. 8, taken along line 9-9;

FIG. 10 is a schematic cross-sectional diagram of the mold shown in FIG.8, taken along line 10-10;

FIG. 11 is a schematic cross-sectional diagram of one embodiment ofinjection molding nozzles inserted within a mold;

FIG. 12 is a schematic cross-sectional diagram of the mold shown in FIG.11 as the mold is being filled to form one embodiment of an inner soleboard, taken along line 12-12;

FIG. 13 is a schematic cross-sectional diagram of a mold as the mold isbeing filled to form another embodiment of an inner sole board;

FIG. 14 is a schematic cross-sectional diagram of a filled moldcontaining another embodiment of an inner sole board;

FIG. 15 is a schematic cross-sectional diagram of a filled moldcontaining another embodiment of an inner sole board;

FIG. 16 is a schematic cross-sectional diagram of a filled moldcontaining another embodiment of an inner sole board; and

FIG. 17 is a schematic isometric view of an embodiment of a group ofinner sole boards that may be provided as a kit with an article offootwear.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An inner sole board having varying regions of flexibility is providedfor use in an article of footwear. A method of making the inner soleboard is also provided. In some embodiments, the inner sole board may becustomized to a desired flexibility for a particular sport orindividual.

Generally, the flexibility of an object may be changed by alteringdifferent features or aspects of an object. These features may includethe length, width, thickness, and shape of the object. Flexibility mayalso be changed by altering the material properties of the object. Forexample, in one embodiment, the object may be made of a first material.In another embodiment, the object may be made of a second, softermaterial. In yet another embodiment, the object may include one or morematerials of varying rigidity at various locations within the object.

The inner sole board may include different materials along its length atdifferent locations that vary its flexibility along its length. Oneregion of the inner sole board may include a different material than therest of the inner sole board, or the inner sole board may includemultiple regions having different materials.

The inner sole board may be positioned in a sole of an article offootwear 100. FIG. 1 is a schematic isometric view of one embodiment ofa cleated article of footwear. Cleated article of footwear 100 mayinclude a cleated sole 101 attached to an upper 103.

Upper 103 may be any type of upper known in the art. Upper 103 isdepicted as having a substantially conventional configurationincorporating a plurality of material elements (e.g., textiles, foam,leather, and synthetic leather) that are stitched or adhesively bondedtogether to form an interior void for securely and comfortably receivinga foot. Given that various aspects of the present application primarilyrelate to sole 101, upper 103 may exhibit the general configurationdiscussed above or the general configuration of practically any otherconventional or non-conventional upper. Accordingly, the structure ofupper 103 utilized with sole 101 or variants thereof may varysignificantly.

In some embodiments, the inner sole board may comprise a part of cleatedsole 101. However, in other embodiments, the inner sole board may beincorporated into the soles of different types of articles of footwear.For example, the inner sole board may be incorporated into a hiking shoeor a dress shoe.

FIG. 2 is a schematic isometric exploded view of an embodiment of acleated sole 101 incorporating an inner sole board 104. Cleated sole 101may be a layered sole including a sock liner 102, an inner sole board104, and a cleat plate 106. Sock liner 102 may be a first layerconfigured to be in contact with a wearer's foot and a second layer,inner sole board 104. Sock liner 102 may be made of a soft material toprovide additional comfort to a wearer's foot and/or wick moisture awayfrom the wearer's foot. In some embodiments, sock liner 102 may beremovably attached to cleated sole 101. However, in other embodiments,sock liner 102 may not be removable.

Cleat plate 106 may be a third layer configured to be in contact withinner sole board 104 and the ground. Cleat plate 106 may include one ormore cleats 112 for gripping the ground.

Inner sole board 104 may provide additional support for a wearer's foot.Inner sole board 104 may generally be a layer of material formed toalign with the contours of the wearer's foot. Inner sole board 104 maybe stiffer or more rigid than sock liner 102. In some embodiments, innersole board 104 may be removable from cleated sole 101. However, in otherembodiments, inner sole board 104 may not be removable.

Inner sole board 104 may be described as having a forefoot region 108, amid-foot region 109, and a heel region 111. The desired stiffness ofeach region may vary for a particular activity or individual. Forexample, in some embodiments, it may be desirable to change theflexibility of inner sole board 104 in forefoot region 108. In theexemplary embodiment shown in FIG. 2, forefoot region 108 may have aforefoot flex zone 110 that causes forefoot region 108 to be moreflexible than the remainder of inner sole board 104.

FIG. 3 is a schematic isometric view of one embodiment of inner soleboard 104. FIG. 4 is a schematic longitudinal cross-sectional diagram ofinner sole board 104, taken along line 4-4. FIG. 5 is a schematicenlarged transverse cross sectional diagram of inner sole board 104,taken along line 5-5. Inner sole board 104 may generally include tworegions: a forefoot flex zone 110 or first portion and an inner solebody 209 or second portion. Forefoot flex zone 110 may be positioned inforefoot region 208. Inner sole body 209 may provide the remainder ofinner sole board 104. Inner sole body 209 and forefoot flex zone 110 maybe made from different materials. Forefoot flex zone 110 may primarilyinclude a first material 211, and inner sole body 209 may primarilyinclude a second material 213.

In some embodiments, first material 211 may be positioned on inner soleboard 104 so that second material 213 surrounds at least a periphery offirst material 211 at forefoot region 108. In some embodiments, firstmaterial 211 may have a different stiffness than second material 213.For example, first material 211 may be less stiff, i.e., more flexible,than second material 213. The resulting configuration provides increasedflexibility in forefoot region 108. When installed in an article offootwear, for example article of footwear 100, and used by the wearer,the increased flexibility in forefoot region 108 results in a trampolineeffect or a multidirectional spring loaded response in forefoot region108. Therefore, when the wearer's weight pushes on forefoot region 108,forefoot region 108 may bend or bow slightly, particularly at or nearforefoot flex zone 110. However, the stiffness of forefoot region 108due to second material 213, which is stiffer than first material 211,may inhibit over flexing. Therefore, injury to the wearer's foot may beavoided. When the wearer pushes off from the ground, the energy storedin the bending of forefoot region 108 may be released in a spring-likeaction to assist the wearer. This may help prevent the wearer's footfrom becoming tired.

Inner sole board 104 may be customized by varying the size and shape offorefoot flex zone 110. A larger flex zone 110, i.e., a flex zone 110that occupies a relatively large percentage of forefoot region 108, mayprovide greater flexibility in forefoot region 108. For example, alarger forefoot flex zone 110 may be used in a soccer cleat where arelatively flexible forefoot region 108, relatively rigid mid-footregion 109, and relatively rigid heel region 111 are desirable.

The flexibility of inner sole board 104 in forefoot region 108 may alsobe varied by changing the characteristics of material 211. In differentembodiments, the flexibility characteristics, chemical composition,shape, thickness, and location of first material 211 with respect tosecond material 213 may vary. The flexibility of first material 211 maybe such that it increases the flexibility of inner sole board 104 inforefoot region 108. Therefore, first material 211 may be less stiffthan second material 213. However, in other embodiments, it may bedesirable for first material 211 to be stiffer than second material 213so that first material 211 increases the rigidity of inner sole board104 in forefoot region 108.

First material 211 may be any material that can mechanically and/orchemically bond with second material 213. First material 211 and secondmaterial 213 may be selected to be compatible for bonding purposes.Preferably, first material 211 is chemically similar to second material213 in that first material 211 and second material 213 may have one ormore of the same basic components. For example, in some embodiments,first material 211 may be a copolymer polypropylene, and second material213 may be a polypropylene with glass. However, in other embodiments,first and second materials 211, 213 having different chemicalcompositions may be utilized.

FIG. 5 shows a schematic representation of bonding zone 219. Themagnified area in FIG. 5 shows bonding zone 219 as a region where firstmaterial 211 and second material 213 meet and mechanically and/orchemically bond. Bonding zone 219 is shown exaggerated in size fordescription purposes. Bonding zone 219 may begin to develop whenmaterials 211, 213 are in a molten state. Bonding zone 219 thensolidifies when materials 211, 213 are cured. Although, bonding zone 219is shown as a smooth curve, bonding zone 219 may include irregular orjagged boundaries. In some embodiments, compatible materials may beselected to improve the chemical bonding between first material 211 andsecond material 213. The formation of a mechanical and/or chemical bondbetween compatible materials, first material 211 and second material213, may increase the durability of inner sole board 104 by reducing thelikelihood that first material 211 splits or separates from secondmaterial 213 over time.

The shape of first material 211 may be any shape that increases theflexibility of inner sole board 104 in the region where first material211 is located. In the exemplary embodiment shown in FIG. 3, firstmaterial 211 creates flex zone 110 that is circular in shape. However,in other embodiments, the shape of first material 211 may be any shapecreated by controlling the material flow rates of one or more injectionmolding nozzles.

A first thickness 215 of first material 211 may be any desired thicknessthat can be accommodated in a mold and then inserted and used in anarticle of footwear. In an exemplary embodiment shown in FIG. 4, firstthickness 215 of first material 211 is preferably substantially equal tosecond thickness 217 of second material 213 in the proximity of bondingzone 219 where the two materials meet.

The location of first material 211 on inner sole board 104 may alsovary. In some embodiments, first material 211 may be locatedsubstantially centrally within forefoot region 108 of inner sole board104. However, in other embodiments, first material 211 may be located ina different location or in multiple locations. For example, firstmaterial 211 may be located in heel region 111 instead of or in additionto forefoot region 108. In yet other embodiments, first material 211 maybe located more towards lateral side 221 of inner sole board 104 or moretowards medial side 223 (shown in FIG. 3) of inner sole board 104.

Flexibility of inner sole board 104 may also be varied by changing thecharacteristics of second material 213 that makes up inner sole body209. In different embodiments, the material composition, shape, andthickness of second material 213 may vary.

The material composition of second material 213 may be adjustable sothat the stiffness of second material 213 may be increased or decreased.For example, second material 213 may be a polypropylene materialcontaining glass. The percentage of glass in second material 213 may bevaried so that an increase in glass increases the stiffness of secondmaterial 213 and a decrease in glass percentage decreases the stiffnessof second material 213.

Inner sole body 209 generally defines the overall shape of inner soleboard 104. The shape of second material 213 or inner sole body 209 maybe any shape that fits in an article of footwear of the target size. Insome embodiments and like sock liner 102, inner sole body 209 may coversubstantially the entire sole region of an article of footwear. However,in other embodiments, inner sole body 209 may be smaller than the soleregion of an article of footwear. In an exemplary embodiment shown inFIGS. 3-5, the general shape of inner sole body 209 is such that itcurves at the edges to cradle the wearer's foot. However, in otherembodiments inner sole body 209 may not cradle the wearer's foot.

Second thickness 217 of second material 213 may be any desired thicknessthat can be accommodated in a mold and ultimately in the target articleof footwear. Second thickness 217 may vary along the length and width ofinner sole board 104. However, in some embodiments second thickness 217substantially equals first thickness 215 in the proximity of bondingzone 219 where the two materials meet.

Due to the ability to vary the stiffness of first and second materials211, 213, it may be advantageous to provide first material 211 or secondmaterial 213 with different colors. These colors may reflect the levelof stiffness of either material or the glass percentage in secondmaterial 213. This may be done so that individuals at the manufacturingfactory, distributor, retailer, and user may readily determine or verifythe material, flexibility, or stiffness characteristics of the innersole board they possess. A key to the meaning of the different colorsmay be provided.

Inner sole board 104 may be customized by selecting first material 211and the size and shape of flex zone 110 to tune the flexibility of innersole board 104. The flexibility of inner sole board 104 may be tunedduring the manufacturing process. The manufacturing process may be aninjection molding process. FIGS. 6-12 show an embodiment of such aninjection molding process.

Inner sole board 104 may be manufactured in an injection molding processthat requires only one mold. Generally, injection molding is a processof forming objects by heating molding material to a liquid form andinjecting the material into a mold. Typically, co-molding is a type ofinjection molding where more than one material is injected into a moldhaving one cavity. Generally, co-molding is different from an overmolding injection molding process. Over molding involves the use ofmultiple molds that are filled in multiple steps. Inner sole board 104may be manufactured using a co-molding process where the mold has onecavity that receives both materials and both materials may be receivedsimultaneously.

In some embodiments, first material 211 for flex zone 110 and the secondmaterial 213 for inner sole body 209 may be delivered into a singlemold. The mold may be similar to mold 200 shown in FIGS. 7-8 and 10-12.During the injection molding process, the delivery of first material 211may be controlled by one or more nozzles having gates or valves. Thenozzles may be similar to nozzles 242, 243 shown in FIGS. 8-9 and 11.Nozzles 242, 243 may control the flow rate of first material 213 inorder to control the shape and size of flex zone 110. In this manner,inner sole board 104 may be customized for a specific sport orindividual.

FIG. 6 is a schematic diagram of an embodiment of a process for makinginner sole board 104. Referring to FIG. 6, the process for making innersole board 203 may include a first step 225 of providing a mold, asecond step 227 of providing an injection molding assembly, a third step229 of preparing an injection molding assembly and mold, a fourth step231 of injecting material into the mold, and a fifth step 233 ofestablishing the dimensions of a first portion.

In first step 225, a mold 200 may be provided. FIG. 7 is a schematicisometric view of an embodiment of a mold that may be used to injectionmold inner sole board 104 (shown in FIGS. 3-5). Referring to FIG. 7,mold 200 may be used for injection molding manufacturing purposes. Inone embodiment, mold 200 may be used for co-molding purposes. Mold 200may include a first mold portion 202 and a second mold portion 204.First mold portion 202 may have a first mold portion interior face 206provided with a mold recess 208. Mold recess 208 may include a forefootrecess section 210 and a posterior recess section 212. Second moldportion 204 may have second mold portion interior face 214 provided witha mold protrusion 216. In FIG. 7, second mold portion 204 is rotated toclearly show interior face 214. Mold protrusion 216 may include aforefoot protrusion section 218 and a posterior protrusion section 220.Second mold portion 204 may also include a first material interioraperture 222 and a second material interior aperture 224. First materialinterior aperture 222 and second material inlet aperture 224 may beconfigured to introduce first material 211 and second material 213,respectively, to mold 200, as shown in FIGS. 12-13.

FIG. 8 is a schematic isometric view of an embodiment of injectionmolding assembly 232 and mold 200. Referring to FIG. 8, mold 200 may beplaced in a closed position and positioned in proximity to injectionmolding assembly 232. In the closed position, first mold portion 202 andsecond mold portion 204 may be positioned against each other. Secondmold portion exterior face 226 may be oriented toward injection moldingassembly 232. Second mold portion exterior face 226 may include firstmaterial exterior aperture 228 and second material exterior aperture230.

In second step 227, injection molding assembly 232 may be provided.Injection molding assembly 232 may provide first material 211 and secondmaterial 213 to mold 200. Injection molding assembly 232 may includefirst and second barrels 234, 235, platform 236, first and second barrellines 237, 238, assembly body 241, and first and second nozzles 242 and243.

First barrel 234 may be mounted on platform 236. First barrel 234 may becapable of housing and heating first material 211 until first material211 becomes a flowable melt. First barrel line 237 may connect firstbarrel 234 to assembly body 241 at first manifold aperture 239. Assemblybody 241 may connect first barrel line 237 to first nozzle 242. Assemblybody 241 may also be heated so that first material 211 remains in amolten state. First nozzle 242 may be used to inject first material 211into mold 200. Similarly, second material 213 may be housed in secondbarrel 235 that may be mounted on platform 236. Second material 213 maybe heated into a flowable melt. Assembly body 241 may be connected tosecond barrel 235 by second barrel line 237. Through assembly body 241,second barrel line 237 may be connected to second nozzle 243. Secondnozzle 243 may be used to inject second material 213 into mold 200.

FIG. 9 is a schematic cross-sectional diagram of an embodiment of aportion of an injection molding assembly 232. Referring to FIG. 9, firstnozzle 242 and second nozzle 243 may be associated with assembly body241. In some embodiments, nozzles 242, 243 may be disposed at leastpartially inside assembly body 241. However, in other embodiments,nozzles 242, 243 may only be in the vicinity of assembly body 241.

Assembly body 241 may include manifold passages 258 and 280, actuators250 and 272, and control unit 260. Assembly body 241 may include a firstpassage 258 connecting a first manifold aperture 239 to a first internalmanifold aperture 259. First passage 258 may intersect a first bore 288at first internal manifold aperture 259. First bore 288 may open to theexterior of assembly body 241 at first bore aperture 261 and may extendinto assembly body 241 to meet first nozzle actuator 250.

First nozzle 242 may be partially disposed within assembly body 241.First nozzle 242 may extend from first nozzle actuator 250 insideassembly body 241 through first bore aperture 261 to an exteriorenvironment of assembly body 241. First nozzle 242 may be comprised of afirst nozzle shell 244, a first nozzle pin 246, and first nozzle piston248. First nozzle shell 244 may have a first nozzle internal aperture263 that meets first internal manifold aperture 259. Although FIG. 9shows the walls of first bore 288 as spaced from first nozzle shell 244,first nozzle shell 244 may be in contact with the walls of first bore288. First nozzle shell 244 may also includes a first nozzle externalaperture 256 that opens to the exterior of assembly body 241.

The combined motion of first nozzle pin 246 and first nozzle piston 248may control the flow rate of first material 211 through first nozzleexternal aperture 256. First nozzle pin 246 may be extended toward andretracted away from first nozzle external aperture 256. As shown in FIG.9, first nozzle pin includes a first end 252 and a second end 254. Firstnozzle pin first end 252 may close first nozzle external aperture 256when first nozzle pin 246 is fully extended. First nozzle piston 248 mayalso be extended toward and retracted away from first nozzle externalaperture 256. As illustrated in FIG. 9, first nozzle piston 248 remainsin a retracted position when first nozzle pin 246 is in a fully extendedposition.

First nozzle pin 246 and first nozzle piston 248 may be actuated indifferent ways. Actuator 250 may be any type of actuator known in theart. For example, a mechanical, pneumatic, or electrical actuator may beused. Actuator 250 may also be operated by a any method known in theart. For example, actuator 250 may receive a signal through first line262 from control unit 260 indicating the desired movement of firstnozzle pin 246 and first nozzle piston 248. The electrical signal may bereceived by an electric motor (not shown) that mechanically moves firstnozzle pin 246 and first nozzle piston 248 to their desired positions.

Additional passages, bores, and actuators may be similarly positionedand structured to support additional nozzles. For example, assembly body241 may include a second passage 280 connecting a second manifoldaperture 240 to a second internal manifold aperture 281. Second passage280 may intersect a second bore 290 at second internal manifold aperture281. Second bore 290 may open to the exterior of assembly body 241 atsecond bore aperture 283 and may extend into assembly body 241 to meetsecond nozzle actuator 272.

Similar to first nozzle 242, second nozzle 243 may be partially housedwithin assembly body 241. Second nozzle 243 may also include a secondnozzle shell 266, a second nozzle pin 268, and second nozzle piston 270.Second nozzle pin 268 may include a first end 274 and a second end 276.Second nozzle pin first end 274 may close second nozzle externalaperture 278 when second nozzle pin 268 is in an extended position.Second nozzle shell 266 may have a second nozzle internal aperture 285that is in fluid communication with second internal manifold aperture281. Second nozzle shell 266 may also include a second nozzle externalaperture 278 that may be positioned beyond assembly body 241 andinserted into mold 200 (shown in FIG. 11). Second nozzle 243 includes anassociated actuator 272 and may be actuated similarly to first nozzle242 by control unit 260 through an associated second line 282.

In some embodiments, control unit 260 may control the injection moldingassembly 232 by communicating with one or more actuators 250, 272. Inoperation, control unit 260 first determines the desired amount of amolten first material 211 and a desired amount of a molten secondmaterial 213 to be injected into mold 200. Control unit 260 may makethis determination based on input from a local or remote computer (notshown), which indicates at least the desired size and shape of flex zone110. Based on this information, the flow rates of first and secondmaterials 211, 213 through nozzles 242, 243 may be processed and theposition information for first and second nozzle pins 246, 268 and firstand second nozzle pistons 248, 270 are determined. The positioninformation may be transmitted to actuators 250, 272 through lines 262,282 respectively as signals. The signals may initiate actuators 250, 272to move first and second nozzle pins 246, 268 and first and secondnozzle pistons 248, 270 to the desired positions to create the desiredflow rates.

In different embodiments, control unit 260 may include a number of portsthat facilitate the input and output of information and power. The term“port” means any interface or shared boundary between two conductors. Insome cases, ports may facilitate the insertion and removal ofconductors. Examples of these types of ports include mechanicalconnectors. In other cases, ports are interfaces that generally do notprovide easy insertion or removal. Examples of these types of portsinclude soldering or electron traces on circuit boards. Some embodimentsmay include a given port or provision, while others may exclude it.

In third step 229, an injection molding assembly 232 and mold 200 may beprepared. FIG. 10 is a schematic cross-sectional diagram of anembodiment of a mold 200. First mold portion 202 and second mold portion204 may be placed in contact with each other to create closed mold 200.Mold 200 may include a first mold passage 292 that begins at firstexterior mold aperture 228 and extends through second mold portion 204to first interior mold aperture 222. Similarly, mold 200 may include asecond mold passage 294 that begins at second exterior mold aperture 230and extends through second mold portion 204 to second interior moldaperture 224.

First mold portion 202 and second mold portion 204 mate to create a moldcavity 231. In some embodiments, mold cavity 231 may be a result of moldprotrusion 216 being partially inserted into mold recess 208. Theremaining empty space of mold recess 208 generally creates mold cavity231. However, in other embodiments, the positions of mold protrusion 216and mold recess 208 may be reversed so that first mold portion 202includes a protrusion and second mold portion 204 includes a recess. Inyet other embodiments, first mold portion 202 and second mold portion204 each may include a combination of protrusions, recesses, and flatsurfaces depending on the desired shape of an inner sole board.

The portion of mold cavity 231 created by forefoot protrusion 218 andforefoot recess 210 correspond to forefoot region 108 of inner sole body104. The portion of mold cavity 231 created by posterior protrusion 220and posterior recess 212 correspond to mid-foot region 109 and heelregion 111 of inner sole body 104.

FIG. 11 is a schematic cross-sectional diagram of injection moldingnozzles 242, 243 inserted within mold 200. Prior to filling mold 200,injection molding assembly 232 may be moved so that first and secondnozzles 242, 243 may be inserted within passages 258, 280 of mold 200.In some embodiments, first nozzle 242 and second nozzle 243 do notprotrude into cavity 231. However, in other embodiments, nozzles 242,243 may protrude into cavity 231.

In fourth step 229, material may be injected into mold 200. Inoperation, first barrel 234 containing first material 211 may be heatedto melt first material 211. Molten first material 211 then flows throughfirst barrel line 237 and into assembly body 241 as indicated by thearrows in FIG. 11. Finally, first nozzle 242 may controllably injectmolten first material 211 into mold 200. In a similar manner, secondmaterial 213 may be heated in second barrel 235 and injected throughsecond nozzle 243 into mold 200 as indicated by the arrows.

When the injection molding process begins, first and second materials211, 213 may melt and fill first nozzle interior 284 and second nozzleinterior 286, respectively. Actuators 250, 272 may move first nozzle pin246 and second nozzle pin 268 to retracted positions. The actuators mayalso move first nozzle piston 248 and second nozzle piston 270 toextended positions. As first and second nozzle pistons 248, 270 movetoward extended positions, pistons 248, 270 push first and secondmaterials 211, 213 through nozzle outlet apertures 222, 224,respectively, and into cavity 231.

In different embodiments, the flow rate of first and second materials211, 213 may be varied in different ways. In some embodiments, nozzlepins 246, 268 and pistons 248, 270 may be moved to control the flowrates of first and second materials 211, 213, respectively. However, inother embodiments, only nozzle pins 246, 268 may move to control theflow rates of first material and second material 211, 213, respectively.

In fifth step 233, the dimensions of a first portion are established bycontrolling the first nozzle 242 and second nozzle 243. Inner sole board104 pictured in FIGS. 3-5 may be manufactured in the following manner byusing the injection molding setup shown in FIGS. 7-11. In oneembodiment, the injection molding process may be a hot injection moldingprocess that produces a mechanical and/or chemical bond between twodifferent materials.

FIG. 12 is a schematic cross-sectional diagram of mold 200. Process 289shows how mold 200 may be filled to produce inner sole board 104 as timet progresses. First view 293 shows mold 200 at a time t=1. Second view295 shows mold 200 at a time t=1+x. Third view 296 shows mold 200 at atime t=1+y. Fourth view 297 shows mold 200 at a time t=1+z. For thepurposes of this discussion, z>y>x. In first view 293, first material211 begins to occupy forefoot recess 210 and second material 213 beginsto occupy posterior recess 212. In second view 295 first and secondmaterials 211, 213 continue to fill cavity 231. The flow rates of firstmaterial 211 and second material 213 from first view 293 to second view295 remain constant. However, the flow rates of materials 211, 213 maydiffer.

In third view 296, first nozzle 242 associated with first material 211is shut off, but the flow rate of second material 213 has not changed.Second material 213 may contact first material 211 at this time andbegin to surround first material 211. In fourth view 297, cavity 231 maybe filled and second nozzle 243 associated with second material 213 maybe closed.

The dimensions of first portion or forefoot flex zone 110 may beestablished by controlling a first flow rate through first nozzle 242.The dimensions may also be controlled by varying the first nozzle timeon, the time at which first nozzle 242 may be turned on, and the firstnozzle time off, the time at which first nozzle 242 may be turned off.

The dimensions of first portion 110 may also be established bycontrolling a second nozzle time on, the time at which second nozzle 243may be turned on, and a second nozzle time off, the time at which secondnozzle 243 may be turned off. Contact between first material 211 andsecond material 213 may control the size of first portion or forefootflex zone 110. When second material 213 contacts first material 211,second material 213 begins to surround and reduce the spread of firstmaterial 211. Additionally, the temperatures of molten first material211 and molten second material 213 facilitates mechanical and/orchemical bonding between first material 211 and second material 213. Thetemperatures of molten materials 211, 213 are equal to or higher thanthe bonding temperature of materials 211, 213.

In one embodiment, first nozzle 242 and second nozzle 243 may be turnedon simultaneously. In other embodiments, first nozzle time on and secondnozzle time on may be staggered. For example, in one embodiment, firstnozzle 242 may be turned on prior to second nozzle 243. In anotherembodiment, second nozzle 243 may be turned on prior to first nozzle242. The time between first nozzle time on and second nozzle time on mayalso vary. First nozzle time off and second nozzle time off may varysimilarly to first nozzle time on and second nozzle time on. Therefore,in some embodiments, first nozzle time on and first nozzle time offoccur prior to second nozzle time on and second nozzle time off.

Generally, after cavity 231 is filled, mold 200 is moved so that thematerial of inner sole board 104 may cure. The material of inner soleboard 104 may be cured using any method known in the art. For example,inner sole board 104 may be cooled at ambient temperature, undergocontrolled cooling in an oven, ultraviolet curing, or the like. Oncecured, inner sole board 104 may be removed from mold 200.

Inner sole board 104 may have any of a number of differentconfigurations depending upon the desired flexibility characteristics ofinner sole board 104. In some embodiments, inner sole board 104 havingone flex zone 110 may be manufactured using two nozzles to deliver twomaterials. In another embodiment, inner sole board 104 may have two ormore flex zones and may be manufactured in an injection molding processthat uses three or more nozzles to deliver two or more materials intoone mold.

FIG. 13 is a schematic cross-sectional diagram of an embodiment of amold fitted with three nozzles. Referring to FIG. 13, process 300 showshow second mold 301 may be filled to produce second inner sole board 304having two flex zones 317, 319 and inner sole body 309 as time tprogresses. A first flex zone 317 may be positioned in the forefootrecess 310 and a second flex zone 319 may be positioned in posteriorrecess 312. First flex zone 317 may be substantially coextensive withforefoot recess 310 and therefore, substantially coextensive with theforefoot region of inner sole board 304.

First view 320 shows mold 301 at a time t=1. Second view 322 showssecond mold 301 at a time t=1+x. Third view 324 shows second mold 301 ata time t=1+y. Fourth view 326 shows mold 301 at a time t=1+z. For thepurposes of this discussion, z>y>x. In first view 320, first material311, second material 313, and third material 315 begin to occupyforefoot recess 310 and posterior recess 312. In this embodiment, firstmaterial 311 and third material 315 may be the same material whilesecond material 313 may be a different material. The flow rates offirst, second, and third materials 311, 313, 315 may remain constant butmay not equal each other.

In second view 322 first and second materials 311, 313 continue to fillrecesses 310, 312. However, third material 315 has ceased flowing. Theflow rates of first and second materials 311, 313 remain constant fromviews 320 to 322. However, the flow rates of materials 311, 313 are notthe same. In third view 324, the nozzle associated with first material311 may be shut off, but second material 313 may continue to flow.Second material 313 may contact first material 311 and third material315 at this time and begin to surround both materials 311, 315. Infourth view 326, the open portions of forefoot recess 310 and posteriorrecess 312 may be filled, and the nozzle associated with second material313 may be closed. Similar to nozzles 242, 243, the three nozzlesassociated with mold 301 may have varying nozzle time on and nozzle timeoff sequences.

In another embodiment, a third inner sole board 404 may be manufacturedin third mold 401 having two flex zones 417, 419 in the forefoot regionand inner sole body 409. FIG. 14 is a schematic cross-sectional diagramof an embodiment of a mold fitted with three nozzles. Referring to FIG.14, view 400 shows a filled third mold 401. A first nozzle may beassociated with first material 411, a second nozzle may be associatedwith second material 415, and a third nozzle may be associated withthird material 413. In this embodiment, materials 411 and 415 may be thesame material or different materials while third material 413 may bedifferent from both first and second materials 411, 415. Similar tonozzles 242, 243, the three nozzles associated with mold 401 may havevarying nozzle time on and nozzle time off sequences.

In another embodiment, a fourth inner sole board 504 may be manufacturedin fourth mold 501 having flex zone 517 in forefoot region 510. FIG. 15is a schematic cross-sectional diagram of an embodiment of a mold fittedwith three nozzles. Referring to FIG. 15, view 500 shows filled fourthmold 501. A first nozzle may be associated with first material 511, asecond nozzle may be associated with second material 513, and a thirdnozzle may be associated with third material 515. In this embodiment,materials 511 and 515 may be the same material or different materialswhile third material 513 may be different from both first and secondmaterials 511, 515. Additionally, in this embodiment, the nozzlesassociated with materials 511, 515 remain open until enough material isdelivered to produce a forefoot flex zone 517 shaped as a figure eight.Here, the circular pattern formed by each nozzle blend together oroverlap slightly to form a figure eight. Similar to nozzles 242, 243,the three nozzles associated with mold 501 may have varying nozzle timeon and nozzle time off sequences.

In another embodiment, as shown in FIG. 16, a fifth inner sole board 604may be manufactured in fifth mold 601 having one flex zone 617 inforefoot region 610. First and second nozzles may be associated withfirst material 611 and second material 615, respectively. A third nozzlemay be associated with third material 613. In this embodiment, materials611 and 615 may be the same material or different materials while thirdmaterial 613 may be different from both first and second materials 611,615. Additionally, in this embodiment, the nozzles associated with firstand second materials 611, 615, remain open until enough material may bedelivered to produce forefoot flex zone 617 of an oblong shape. Here,circular pour patterns combine to form an oblong shape. Similar tonozzles 242, 243, the three nozzles associated with mold 301 may havevarying nozzle time on and nozzle time off sequences.

A kit of inner sole boards including one or more sets of inner soleboards may be sold with footwear or separately so that a user may choosean inner sole board with flexibility characteristics for a desiredactivity. For example, one set of inner sole boards may be inserted inan article of footwear for soccer, while another inner sole board sethaving a different flexibility characteristic may be inserted in anarticle of footwear for football. A kit of inner sole boards may also besold with or without associated footwear.

A kit of inner sole boards may include two or more sets of inner soleboards. FIG. 17 is a schematic isometric view of an embodiment of agroup or kit of inner sole boards having various stiffnesses. Referringto FIG. 17, inner sole board kit 700 may include three sets of innersole boards 702, 704, 706. Each set of inner sole boards 702, 704, 706may include different flexibility characteristics.

A First inner sole board set 702 may include forefoot flex zones 707made of a first material 708 and inner sole bodies 709 made of a secondmaterial 710. A second inner sole board set 704 may include leftforefoot flex zone 712 made of a third material 718 and left inner solebody 716 made of a fourth material 714. Second inner sole board set 704may also include a right forefoot flex zone 720 made of a fifth material722 and a right inner sole body 724 made of sixth material 726. A thirdinner sole board set 706 may include a left forefoot flex zone 728 madeof a seventh material 730 and a left inner sole body 732 made of aneighth material 734. A third inner sole board set 706 may also include aright forefoot flex zone 736 made of a ninth material 736 and a rightinner sole body 740 made of a tenth material 742.

First material 708, third material 714, fifth material 722, seventhmaterial 722, and ninth material 736 may be the same material ordifferent materials. For example, first material 708 may be more rigidthan third material 714, and third material 714 may be more rigid thanseventh and ninth materials 722, 736.

Second material 710, fourth material 718, sixth material 726, and eighthmaterial 742 may be the same material or different materials. If theyare the same material, the flexibility of each inner sole board set maybe altered by changing the shape of the associated flex zones. In theexemplary embodiment shown in FIG. 17, flex zone 707 may be shaped as acircle, flex zones 720, 736 may have an oblong shape, and flex zones714, 720 may cover almost an entire forefoot region.

An individual may choose an inner sole board set where the left innersole board has the same flexibility characteristics as right inner soleboard. Alternatively, as shown by inner sole board sets 704, 706, leftand right inner sole boards may differ to match the desired flexibilitycharacteristics of each foot.

In other embodiments, kit 700 may include a group of inner sole boardsthat include only left-foot inner sole boards or only right-foot innersole boards. In yet other embodiments, kit 700 may include a group ofinner sole boards including left-foot inner sole boards and right-footinner sole boards where no inner sole board in the group has flexibilitycharacteristics similar to the inner sole boards in the remainder of thegroup.

While various embodiments of the invention have been described, thedescription is intended to be exemplary, rather than limiting and itwill be apparent to those of ordinary skill in the art that many moreembodiments and implementations are possible that are within the scopeof the invention. Accordingly, the invention is not to be restrictedexcept in light of the attached claims and their equivalents. Also,various modifications and changes may be made within the scope of theattached claims.

1. An inner sole board for an article of footwear comprising: a firstportion comprising a first material; a second portion comprising asecond material; a bonding zone disposed where the first portion and thesecond portion meet; the first material having different flexibilitycharacteristics than the second material; wherein a size and a locationof the first portion with respect to the second portion is configured toconform to a set of flexibility characteristics associated with anactivity; and wherein the bonding zone comprises a bond between thefirst material and the second material that is initiated when the firstmaterial and second material are in a molten state.
 2. The inner soleboard of claim 1 wherein the first portion is disposed in a forefootregion of the article of footwear.
 3. The inner sole board of claim 1,wherein the first portion is disposed in a heel region of the article offootwear.
 4. The inner sole board of claim 2, comprising: the firstportion having a first thickness; the second portion having a secondthickness; and wherein the first thickness and the second thickness aresubstantially equal proximate the bonding zone.
 5. The inner sole boardof claim 4, wherein the first portion has a circular shape.
 6. The innersole board of claim 4, wherein the first portion is substantiallycoextensive with the forefoot region.
 7. A kit for customizing anarticle of footwear comprising: a group of inner sole boards; whereineach inner sole board of the group of inner sole boards is configured tobe removably inserted into the article of footwear; wherein each innersole board has a unique flexibility characteristic; and wherein eachinner sole board comprises a first portion comprising a first material;a second portion comprising a second material; a bonding zone disposedwhere the first portion and the second portion meet; the first materialhaving different flexibility characteristics than the second material;wherein a size and a location of the first portion with respect to thesecond portion is configured to conform to a set of flexibilitycharacteristics associated with an activity; and wherein the bondingzone comprises a bond between the first material and the second materialthat is initiated when the first material and second material are in amolten state.
 8. The kit of claim 7, wherein the group of inner soleboards comprise left-foot inner sole boards.
 9. The kit of claim 7,wherein the group of inner sole boards comprise right-foot inner soleboards.
 10. The kit of claim 7, wherein the kit comprises left-footinner sole boards and right-foot inner sole boards.
 11. A method ofmaking an inner sole board comprising the steps of: providing a moldhaving a single cavity; providing an injection molding assemblycomprising a first nozzle and a second nozzle; injecting into the cavitya first molten material through the first nozzle and a second moltenmaterial through the second nozzle so that the first molten materialforms a first portion of the inner sole board and the second moltenmaterial forms a second region of the inner sole board; and establishingdimensions of the first portion by controlling the first nozzle.
 12. Themethod of claim 11, wherein the dimensions of the first portion areestablished by controlling a first flow rate through the first nozzle.13. The method of claim 12, wherein the dimensions of the first portionare established by controlling a first nozzle time on and a first nozzletime off.
 14. The method of claim 13, wherein the dimensions of thefirst portion are established by controlling the second nozzle.
 15. Themethod of claim 14, wherein the dimensions of the first portion areestablished by controlling a second nozzle time on and a second nozzletime off.
 16. The method of claim 15, wherein the dimensions of thefirst portion are established by staggering the first nozzle time on andthe second nozzle time on.
 17. The method of claim 16, wherein thedimensions of the first portion are established by staggering the firstnozzle time off and the second nozzle time off.
 18. The method of claim17, wherein first material and second material form a bond in a bondingzone at a temperature greater than or equal to a bonding temperature.19. The method of claim 18, wherein the first material and the secondmaterial are delivered into the cavity simultaneously.
 20. The method ofclaim 19, wherein the bond is selected from the group consisting of achemical bond and a mechanical bond.